When using a network of a mobile network operator (MNO), subscribers may encounter the following situation: when a subscriber that belongs to an MNO1 (for example, China Mobile) but does not belong to an MNO2 (for example, China Unicom) moves to a location (for example, a blind area of the MNO1) not covered by an MNO1 signal but covered by an MNO2 signal, the subscriber cannot continue to use a network of the MNO1 to perform communication, which causes great inconvenience to the subscriber especially if the subscriber has an important call.
To deal with this situation, the prior art puts forward a solution for temporarily using another MNO. When a user equipment (UE) detects a loss of contact with the current MNO network, the UE notifies an embedded universal integrated circuit card (eUICC) that is embedded in the UE about another available MNO detected by the UE, where the other available MNO may be referred to as a second operator network, and the network with which the UE has lost contact may be referred to as a first operator network. The eUICC learns a remote management platform of the second operator network according to information about the second operator network provided by the UE, where the remote management platform includes a subscription manager-secure routing unit (SM-SR) and a subscription manager-data preparing unit (SM-DP). Then, the eUICC instructs the UE to send a request for temporary operational profile (OP) to the SM-SR, where the OP is a series of files required for using an MNO network. The SM-SR of the second operator network requests a temporary OP from the SM-DP after the eUICC is authenticated by an SM-SR of the first operator network. The SM-DP allocates a temporary OP, and sends the temporary OP to the eUICC through the SM-SR of the second operator network. The eUICC instructs the UE to access the second operator network using the temporary OP, so that the UE begins to use the second operator network without having to miss important calls.
There is a need for a method whereby the UE can switch from the second operator network back to the first operator network when network signals of the first operator network are recovered.